I’ve just written a LowLevelGraphicsContext that uses CoreGraphics to do its rendering.
Actually turned out to a lot easier than I expected, just a few hours work - it’s checked it in, and is set to be the default renderer for component painting. (If you’re rendering into an Image, the old software renderer is still used).
In the juce demo everything seems to look correct. Strangely, some things render much faster than the old renderer (e.g. image rescaling), and others not so well (e.g. complex Drawables). but I’d be interested to hear if it works in your projects… If it fails disastrously or has lousy performance, you can easily disable it with the USE_COREGRAPHICS_CONTEXT flag in juce_mac_NSComponentPeer.mm
It’s only a first pass, and next I’ll be refactoring the design of the LowLevelGraphicsContext class to make a better fit with native contexts, which should speed things up…